EFFECTS ON ELEVATED PLUS-MAZE BEHAVIOR OF EXPOSURE TO CAFFEINE DURINGBOTH GESTATION AND LACTATION

Eight to 9 months after exposure to gestational and lactational doses of either 26/45 (low dose) or 25/35 (high dose) mg/kg/day of maternall y ingested caffeine (via drinking water), rats were observed in an ele vated plus-maze. The highest level of caffeine exposure decreased tota l rearing and increased immobility, and increased entries and occupanc y of the open arms. Differences between the open and the preferred enc losed arms in frequencies of entries, occupancy, and walking were also greatest for rats exposed to the highest level of caffeine, and adren al gland weights relative to body weight were highest for males in thi s group. Although some of the results support earlier reports of long- lasting heightened emotional reactivity following perinatal caffeine e xposure, others did not. It was suggested that preexperimental and tes ting procedures may have provided a situation less aversive than those in which perinatal caffeine effects have been observed previously. Tr eatment effects on open-arm behavior might have arisen from impaired s patial ability.